Attachment for booms



Aug. 15, 1939. 1 CLARK 2,169,556

ATTACHMENT FOR BOOMS Filed April 30, 1958 Patented Aug. 15, 1939 PATENT OFFICE ATTACHMENT FOR BOOMS George J. Clark, Haworth, N. J.

Application April 30,

4 Claims.

This invention relates to an improved attachment for booms and is particularly designed to provide means for mounting a wide sheave on a boom of the type constructed to employ a narrow sheave.

The narrow sheave type is a common mechanism employed on booms of various kinds but the particular form herein referred to is that used on stacking machines such as used on docks. In some instances it is necessary or desirable to carry bundles or cases to a height nearly as high as the end of the boom. The advantage of this is to allow stacking which adds a tier or two to the pile or stack. The method of doing this is to provide a wide sheave which allows the hook on the end of the hoist line and the sling rope on the hook to pass over the pulley. This form of lift is employed on cranes of various types and also in logging mechanism. The above devices are old and well-known.

The present improvement is one designed to allow transformation of a narrow sheave boom to a wide sheave boom and this in a short space of time and therefore little interference with operations. The device of this invention is one having a means for support on the end of the boom, usually by simply removing the narrow sheave and utilizing the holes used as bearings, for bolts supporting the attachment. The attachment is provided with a wide sheave and elements for preventing entanglement of slack ropes or lines with the sheave.

The invention is illustrated in the accompanying drawing in which Figure l is a side view of the end of a boom with my improved attachment. Figure 2 is a side view of the boom of the type for which the attachment is designed. Figure 3 is a longitudinal central section of a fixture embodying my invention. Figure 4 is a top view of the fixture illustrated in Figure 3. Figure 5 is a section on line 55 in Figure 4 and Figure 6 is a section on line 6-6 in Figure 3.

In the drawing I illustrate a conventional form of boom l0 which may be used with a narrow sheave l l rotating between the sides of the boom and mounted on the pin or shaft I2 which passes through the boom. When the boom is to be fitted with the wide sheave attachment the sheave II and shaft [2 are removed, which is simple as the shaft is usually a bolt with nuts on the ends and when the nuts are unscrewed the bolts can be withdrawn and the sheave taken out.

My attachment can then be installed. The attachment is in the form of a single fixture which includes a socket M which has the outer walls 1938, Serial No. 205,144

wide sheave 22 and is held in place by the nut 23, the side walls having curved beads 24 adjacent the ends of the sheave to insure the rope remaining on the sheave. The top Wall of the socket is extended to form a guard 25 on the inner side relative to the sheave 22 which guard prevents a slack line from becoming entangled with the sheave or prevents the hook usually employed from dropping down between the sheave and the socket.

Beyond the side walls I9 is a guide 26 in the form of a loop. This guide prevents the line or hook from getting entangled by keeping it within bounds beyond the sheave. The fixture is compact and is readily installed or removed. In some instances, more fastening means is advisable Which is provided by the bolts 2'! fitting through the holes 28 in the boom and the holes 29 in the socket.

In using this fixture the line 30, the hook 3| and the sling rope 32 can pass over the sheave 22 and thus carry the hoisted article 33 to higher level than with the narrow sheave I I over which the hook 3| can not pass.

Various changes can be made in the form and proportion of parts without departing from the scope of my invention as set forth in this specification and also embodied in the claims.

I claim:

1. An attachment for booms comprising a fixture having a socket on one end for receiving the end of a boom, the fixture having divergent upwardly inclined walls extending therefrom, a guard bridging the walls, the Walls also serving as bearings and a Wide sheave supported in the bearings.

2. An attachment for booms comprising a fixture having a socket on one end for receiving the end of boom, the fixture having divergent upwardly inclined walls extending therefrom, a guard bridging the Walls, the walls also serving as bearings and a looped guide bridging the walls beyond the sheave.

3. The combination of a boom of the narrow sheave type having aligned openings for reception of the shaft of the sheave, with a fixture comprising a socket for receiving the end of the boom and having opening aligned with the openings on the boom when the socket embraces the end of the boom, the fixture having divergent side walls forming bearings for a wide sheave, a wide sheave supported in said bearings and a guard bridging said walls and arranged in extension of the top part of the socket.

4. The combination of a boom of the narrow sheave type having aligned penings for reception of the shaft of the sheave, with a fixture comprising a socket for receiving the end of the boom and having openings aligned with the openings in the boom when the socket embraces the end of the boom, the fixture having divergent side walls forming bearings for a wide sheave, a wide sheave supported in said bearings, a guard bridging said Walls and arranged in extension of the top part of the socket and a guide bridging the walls and looped to extend beyond the sheave to provide a clearance.

GEORGE J. CLARK. 

